| Age of the Marwar Supergroup,NW India:A note on the U–Pb geochronology of Jodhpur Group felsic volcanics |
| |
| 作者姓名： | Huiru Xu Joseph G.Meert Manoj K.Pandit |
| |
| 作者单位： | Hubei Subsurface Multi-scale Imaging Key Laboratory;Department of Earth and Planetary Sciences;Department of Geology |
| |
| 基金项目： | JGM by the US National Science Foundation Grant EAR09-10888;HRX by the National Natural Science Foundation of China Grant 41974078。 |
| |
| 摘 要： | The Marwar Supergroup(NW Peninsular India)is thought to be of Ediacaran-Cambrian age,based on previous paleontological and geochronological studies.However,direct constraints on the onset of sedimentation within the Marwar basin are still scarce.In this study,we report U–Pb zircon,LA-ICP-MS,and SIMS ages from the Chhoti Khatu felsic volcanic rocks,interlayered with the Jodhpur Group sandstones(Lower Marwar Supergroup).The cathodoluminescence images of the zircons indicate complex morphologies,and core-rim textures coupled with the wide range of ages indicate that they are likely inherited or in the case of thin poorly indurated ash-beds,detrital in origin.The age spectra of 68 zircon analyses from our sampling display a dominant 800–900 Ma age peak corresponding to the age of basement"Erinpura granite"rocks in the region.The youngest inherited zircon from a felsic ash layer yielded a U–Pb age of651 Ma±18 Ma that,together with previous studies and paleontological evidence,indicates a postCryogenian age for the initiation of Marwar sedimentation following a~125 Ma hiatus between the end of Malani magmatism and Marwar deposition.
|
| 关 键 词： | Marwar Supergroup Sedimentation age Zircon U-Pb dating Chhoti Khatu felsic volcanics |
| 本文献已被 维普 等数据库收录！ |
| 点击此处可从《地学前缘(英文版)》浏览原始摘要信息 |
| 点击此处可从《地学前缘(英文版)》下载免费的PDF全文 |
